Kelly Chibale is a professor of organic chemistry at the University of Cape Town in South Africa and director of the Cape Town Drug Discovery and Development Center. He is senior author of a study describing the work in the journal Science Translational Medicine.

In animal trials, Chibale said MMV048 cured 100 percent of mice that were infected with malaria.

It was shown to wipe out an infection in three days, said Chibale, adding, “Overall, it presents an exciting profile in terms of the potential to contribute to malaria eradication.”

FILE - A doctor tests a child for malaria at a hospital in Arusha, Tanzania, May 11, 2016. The parasitic illness is responsible for about 425,000 deaths annually, most of them children in sub-Saharan Africa.

And, MMV048 completely protected monkeys that received a dose of the compound. Researchers were unable to infect them, according to Chibale, who said he hopes the experimental drug has the same effect in humans.

“It’s present in the body in the blood already," he explained, "so even when you get bitten by a mosquito, the parasites that initially end up in the blood they will find the drug already waiting for them and they’ll be killed off before they increase in population.”

In the animal studies, Chibale said the compound lasted for at least eight days in the bloodstream, acting as a shield against infection.

Not a vaccine

Chibale is quick to caution that the compound is not a vaccine, which stimulates the immune system to afford long-lasting protection against a pathogen. Development of a vaccine against malaria has been a difficult and frustrating process.

Instead, Chilabe said, MMV048 targets a protein that the parasite needs to protect itself from the immune system.

The parasites are destroyed in the liver, said Chilabe, the first place they travel after someone is bitten by an infected mosquito.

The parasites are thus prevented from migrating into the bloodstream where they infiltrate red cells by the thousands, maturing into a form that can be transmitted back to mosquitoes.

Chibale said MMV048 appears to be effective against parasites that have become resistant to existing drugs.

But he said the drug, in all likelihood, would have to be used as part of drug cocktail with existing anti-malarials to prevent the development of drug resistance.

Early clinical trials show that the compound is safe in healthy humans.

The next stage of clinical trials – to begin testing MMV048’s effectiveness in humans infected with malaria – is likely to begin later this year. Human trials will determine the drug’s proper dose and how often it needs to be given to protect against malaria.